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Glucose Metabolism Effects of Vitamin D Supplementation in Prediabetes (VitDmet)

This study has been completed.
Academy of Finland
Juho Vainio Foundation
Finnish Foundation for Cardiovascular Research
Diabetes Research Foundation, Finland
Information provided by (Responsible Party):
Tomi-Pekka Tuomainen, University of Eastern Finland Identifier:
First received: August 29, 2011
Last updated: March 3, 2013
Last verified: March 2013

Vitamin D deficiency is widespread throughout the world, and the deficiency has been associated with several chronic diseases, such as cardiovascular diseases and diabetes. In Nordic countries, like in Finland, there is a particular variation in vitamin D status, and during wintertime, when there is no exposure to ultraviolet-B light from the sun, serum concentrations of vitamin D decrease substantially. In Finland, some 40% of middle-aged men and one third of women also have some degree of impairment of glucose metabolism.

The purpose of this trial is to investigate the effects of two different daily doses of vitamin D on glucose metabolism in men 60 years of age or older and who are vitamin D deficient, have a high body mass index and at least two characteristics of cardio-metabolic syndrome.

Altogether 102 subjects with low serum calcidiol (<60 nmol/L) will be recruited and randomized to one of the three groups: 1) 40 µg/d vitamin D3, 2) 80 µg/d vitamin D3 or 3) placebo. The supplementation period will last for 6 months from September 2011 to March 2012.

The main hypotheses of the trial are: (1.) Vitamin D supplementation will improve glucose and insulin metabolism in people with a low baseline vitamin D status, in a dose-dependent manner. (2.) Vitamin D supplementation will have an effect on the expression of genes involved in glucose and insulin metabolism and inflammation. (3.) Vitamin D supplementation will have an effect on epigenetic changes in key genes participating in vitamin D metabolism.

Condition Intervention
Prediabetic State
Dietary Supplement: Vitamin D3
Dietary Supplement: Placebo
Dietary Supplement: Vitamin D 80

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Basic Science
Official Title: Randomized Controlled Trial of Vitamin D Supplementation on Glucose Metabolism in Subjects With Components of the Metabolic Syndrome

Resource links provided by NLM:

Further study details as provided by University of Eastern Finland:

Primary Outcome Measures:
  • Insulin sensitivity [ Time Frame: Six months ]
    Change in insulin sensitivity measured by oral glucose tolerance test at baseline and after 6 months

Secondary Outcome Measures:
  • Peripheral blood mononuclear cell gene expression [ Time Frame: Six months ]
  • Inflammation [ Time Frame: Baseline to six months ]
    Change in inflammation measured as serum cytokines and adipose tissue inflammation at baseline and after 6 months

  • Adipose tissue gene expression [ Time Frame: Six months ]

Enrollment: 73
Study Start Date: September 2011
Study Completion Date: May 2012
Primary Completion Date: May 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Vitamin D 40
Vitamin D3 40 micrograms (1600 IU) per day
Dietary Supplement: Vitamin D3
Vitamin D3 40 micrograms (1600 IU) per day
Experimental: Vitamin D 80
Vitamin D3 80 micrograms (3200 IU) per day
Dietary Supplement: Vitamin D 80
Vitamin D3 80 micrograms (3200 IU) per day
Placebo Comparator: Placebo Dietary Supplement: Placebo
Inactive placebo


Ages Eligible for Study:   60 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Age 60 years or older
  • Serum calcidiol <75 nmol/L
  • Body mass index 25-35 kg/m2
  • Impaired fasting glucose or impaired glucose tolerance (fasting glucose 5.6-7.0 mmol/L or 2h oral glucose tolerance test glucose 7.8-11.0 mmol/L)

Exclusion Criteria:

  • Any chronic disease and condition, which may hamper to follow the intervention protocol (such as alcohol abuse)
  • Any chronic disease or therapy which may mask or interact with the investigated effects (such as diabetes or systemic corticosteroid therapy)
  • Any disease or state that raises a vitamin D related safety concern (such as chronic liver, thyroid or kidney disease, hypercalcemia, sarcoidosis or other granulomatous diseases such as active chronic tuberculosis or Wegener's granulomatosis)
  • Use of supplements yielding vitamin D over 20 µg/d and unwillingness to discontinue the use.
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Please refer to this study by its identifier: NCT01479933

University of Eastern Finland, Kuopio Campus
Kuopio, Finland, 70211
Sponsors and Collaborators
University of Eastern Finland
Academy of Finland
Juho Vainio Foundation
Finnish Foundation for Cardiovascular Research
Diabetes Research Foundation, Finland
Principal Investigator: Tomi-Pekka Tuomainen, MD, PhD University of Eastern Finland
  More Information

Additional Information:
Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Tomi-Pekka Tuomainen, Professor, University of Eastern Finland Identifier: NCT01479933     History of Changes
Other Study ID Numbers: VitDmet
Study First Received: August 29, 2011
Last Updated: March 3, 2013

Keywords provided by University of Eastern Finland:
vitamin D
prediabetic state
glucose metabolism
gene expression
immunological function
insulin sensitivity
peripheral mononuclear cells

Additional relevant MeSH terms:
Prediabetic State
Body Weight
Signs and Symptoms
Diabetes Mellitus
Glucose Metabolism Disorders
Metabolic Diseases
Endocrine System Diseases
Vitamin D
Growth Substances
Physiological Effects of Drugs
Bone Density Conservation Agents processed this record on May 22, 2017